Distributed Query Optimization : Can Mobile Agents Help ?

The database eld has developed very powerful techniques for nding eÆcient execution plans for declaratively speci ed queries. However, applying these optimization techniques in the setting of distributed information management requires centralized knowledge. The reality of the Web is di erent. Future distributed query optimizers will have to exploit a rich variety of information ow mechanisms (chaining, referral, proxying, etc.) and must regard the Web as both a repository of information and a computing model. We look to mobile agent technologies for the combination of exibility and precision needed for handling these mechanisms. Our language-based approach uses a mobile process calculus in combination with a powerful query-plan language, so that messaging, migration, and database operations all live in the same semantic space and interact, thus creating new opportunities for optimization.

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